import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.regex.Pattern;

@WebFilter(filterName = "signupFilter",urlPatterns={"/signup"})
public class signupFilter extends HttpFilter {
    @Override
    protected void doFilter(HttpServletRequest req, HttpServletResponse res, FilterChain chain) throws IOException, ServletException {
	
	 Pattern VALID_EMAIL_ADDRESS_REGEX = Pattern.compile("^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,6}$", Pattern.CASE_INSENSITIVE);
	if(req.getParameter("passwd").toString().equals(req.getParameter("confirmpasswd").toString())== false||
	   VALID_EMAIL_ADDRESS_REGEX.matcher(req.getParameter("email")).matches() == false)
	{
	    HttpSession session = req.getSession(true);
	    session.setAttribute("error", "signup");
	    res.sendRedirect("error.jsp");
	}
    }
}
